Rotating x-ray tube

Abstract

An x-ray tube has an evacuated housing rotatable around a rotational axis with a cathode and an anode being rigidly mounted in the housing so as to rotate therewith. The cathode emits electrons which are accelerated with an electrical field so as to strike the anode. An electromagnetic system for deflecting and focusing the electron beam has a number of current-permeated coil elements, whereby the coil elements are arranged a common carrier that at least partially surrounds the housing.

We claim as our invention: 
     
       1. A rotating x-ray tube comprising: an evacuated housing;   drive means for rotating said housing around a rotational axis;   a cathode in said housing which emits electrons;   an anode in said housing at a potential relative to said cathode for causing said electrons to be accelerated from said cathode toward said anode so as to strike said anode and produce x-rays at said anode; and   stationary electromagnetic means for deflecting and focusing said electrons, said electromagnetic means comprising an iron yoke carrier disposed outside of and at least partially surrounding said housing, said carrier supporting a plurality of current-carrying coil elements arranged in a quadrupole arrangement.   
     
     
       2. A rotating x-ray tube as claimed in claim 1 wherein said carrier comprises a substantially cylindrical ring. 
     
     
       3. A rotating x-ray tube as claimed in claim 1 wherein said carrier comprises a plurality of pole projections extending toward said housing, said coil elements being respectively carried by said pole projections. 
     
     
       4. A rotating x-ray tube as claimed in claim 3 wherein said coil elements are wound around respective pole projections. 
     
     
       5. A rotating x-ray tube as claimed in claim 4 wherein each pole projection terminates at an end adjacent said housing, and wherein said coil elements are wound around the respective pole projections at the respective ends thereof. 
     
     
       6. A rotating x-ray tube as claimed in claim 3 wherein said pole projections each has a substantially rectangular cross-section. 
     
     
       7. A rotating x-ray tube as claimed in claim 3 wherein said coil elements and said pole projections are disposed substantially uniformly spaced from each other around said carrier. 
     
     
       8. A rotating x-ray tube as claimed in claim 1 wherein said coil elements are carried by said carrier at respective positions substantially uniformly spaced from each other around said carrier. 
     
     
       9. A rotating x-ray tube as claimed in claim 1 wherein said carrier comprises a single piece. 
     
     
       10. A rotating x-ray tube as claimed in claim 1 wherein said carrier comprises a plurality of pieces joined to each other.